Vented closure

ABSTRACT

This invention relates to a venting plastic liner cap and a twopiece closure for pressurizable containers packaging products such as beer, carbonated beverages and the like. The liner serves to seal the mouth of the container under an outer metal cap provided with a pull tab and tear strip for removal. Pressure is vented through a central aperture of the liner top and into radial channels that extend as the spokes of a wheel. Effective release of internal pressure, upon opening the closure, is provided regardless of where the tear strip of the outer cap is initiated. This construction obviates registration or index of the two parts in closure assembly on the container. Two channel embodiments comprise: (1) a series of depressed radial channels and an outer annular channel interconnected therewith, or (2) a series of radial ribs or projections on the cap that provide radial passageways from the center of the cap; either of these venting gas passing through the center aperture.

United States Patent 1 1 Luczak et al. 1 1 Feb. 20, 1973 [541 VENTEDCLOSURE Primary Examiner-Samuel B. Rothberg [75] Inventors: Terrence L.Luczak; Leonard K. Ass'smm Exammcrflsiephen Marcus u Carlton A. Richie fAttorney-J. Nelson and Holler Toledo Ohm 57 ABSTRACT [73] Assignee:Owens-Illinois, lnc.

This invention relates to a venting plastic liner cap and [22] Film: 1211971 a two-piece closure for pressurizable containers 21 AWL 114,330packaging products such as beer, carbonated beverages and the like. Theliner serves to seal the mouth of the container under an outer metal cappro- [52] 67 1 2; vided with a pull tab and tear strip for removal.Pres- 511 Int. Cl ..B65d '41/20 B65 d 51/16 sum is 9 "T central aperturethe 581 Field of Search ..215/42 36 A 56 4ochanne's as sPkes C 4 of awheel. Effective release of internal pressure, upon opening the closure,is provided regardless of where [561' Rdennces Cited the tear strip ofthe outer cap is initiated. This construction obviates registration orindex of the two UNITED STATES PATENTS parts in closure assembly on thecontainer. Two chan- 1,724,346 8/l929 Ford ..22o/44 A mmpflse (1) aseries dephessed 2,790,570 4/1957 Hodges et a1" "215/56 rad al channelsand an outer annular channel inter- 1,ss9,229 10/1925 Doppke ..2l5/56mnecied therewith, 0r a Series of radial ribs of 3,335,890 8/1967Grundmann et al.. 215/11 R projections on the cap that provide radialpassageways 3,174,641 196$ te a .2l5/56 from the center of the cap;either of these venting gas passing through the center aperture.

, rogge 14 Claims, 6 Drawing Figures PATENTEDFEBZOIUYS I 3,717,276

SHEET 10F z INVENTORS CARLTON A. RICHIE. LEONARD K. PUDLICKI. TERRENCEL. LUCZAK.

ATT'Ys.

PATENTEDFEBZOW I 3.717. 216

I SHEET 2 UF 2 INVENTORS CARLTON A. RICHIE. LEONARD K. PUDLICKI.TERRENCE L. LUCZAK.

VENTED CLOSURE BACKGROUND OF THE INVENTION The invention relates totwo-piece closures of the socalled convenience or easy-open variety.

In this closure, a full fitment plastic liner serves as a gasket or sealand is covered by a metal closure that is fastened onto the finish ofthe container, such as a glass bottle. The metal outer closure is aprescored, convenience type having a tearable top manipulated foropening by an attached pull ring or pull tab of a known variety.

Containers packaging some products, beer and carbonated beverages beingexamples, are to be sealed and thereafter retain certain amounts of gaspressure generated as a beneficial or inherent feature of the product.Upon opening the container for access to the product, the pressurewithin the container will be reduced to atmospheric or nearly so. It isextremely important to be able to control the initial release of gaspressure in the function of opening this type of closure. It is to thisaspect of packaging and closure constructions that this invention isaimed.

In the use of a full liner plastic fitment, proper venting is veryimportant to the function of the closure. For example, upon opening atightly sealed container filled with a carbonated beverage, theaccumulated gas pressure (maybe as high as seven volumes) in the headspace between liner and product is exhausted. If the accumulatedpressure is released all at once, such force may be expended as to sprayproduct from the mouth of the container, and may propel the closuremetal cap and liner as a projectile endangering the user. Thisprojectile reaction may be likened to the flying cork of a champagnebottle when opened.

SUMMARY OF THE INVENTION The venting features of the invention preventsuch inconvenience and hazards from occurring in the opening of thistype packaged product.

As an object of the invention, the liner cap provides vent features foran efficiently controlled, gradual release of gas pressure andeliminates hazards and inconveniences in use of closures of this type.

Another object of this invention is to provide a liner cap with suchventing function that is simple, efficient, and easy and economical tomanufacture and assemble.

DESCRIPTION OF THE DRAWINGS On the drawings:

FIG. 1 is a top plan view, partly broken away and sectioned, of thetwo-piece closure of the invention applied onto a glass bottle;

FIG. 2 is a perspective view of one embodiment of plastic liner cap on abottle finish;

FIG. 3 is a sectional elevational view, taken along line 3-3 on FIG. 1;

FIG. 4 is a top plan view, partly broken away and sectioned, of atwo-piece closure like FIG. 1, but illustrating a second embodiment ofthe liner cap for the invention;

FIG. 5 is a perspective view like FIG. 2, but showing the liner cap ofthis second embodiment; and

FIG. 6 is a sectional elevational view taken along line 66 on FIG. 4.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings,FIGS. 1-6, a two-piece closure cap assembly according to the preferredembodiments of the invention is illustrated as employed in sealing themouth opening of a glass container 10. The mouth is defined by a top rimor bead 11 providing an enlarged side wall flange portion 12 that issloped downwardly and inwardly along the outside of the containerfinish. The closure assembly comprises an inner liner cap 13 made of anelastomeric material, such as polyethylene, plastic composition orrubber composition. Cap 13 includes a disc-like top panel portion 14covering the mouth area inwardly of rim 11. Liner cap 13 is retained onthe rim finish by a radial skirt portion 15 that has a smallest diameteron its inside surface slightly less in dimension than the exteriordiameter of the finish under bead 1 1 of the container. The skirtportion 15 of liner cap 13 is integrally joined with the periphery oftop portion 14 at the corner radius portion 16, and in the embodimentsshown on the drawings, the combination of skirt l5 and corner radius 16forms a groove or seat receiving the rim 11 of the container adapted forsealing the mouth of the container along the top and underside surfacesof the finish 1 1.

Referring now to FIGS. l-3, the first embodiment of the closure isshown. The disc-like portion 14 of liner cap 13 includes a central area17 which is dished concavely and centrally therein is a port or aperture18 providing a vent means through the wall of portion 14 of liner cap13. Outwardly adjacent the perimeter of central area 17 is provided achannel means for conducting gas pressure radially from aperture 18. Thechannel means in this embodiment comprises radial grooves 19 molded inthe disc-like portion 14 of the liner cap. The grooves 19 radiate fromthe central area 17 in a series as the spokes of a wheel. The number andsize of grooves 19 maybe a variable factor in the closure design, butthey should be of sufficient number and size to provide a satisfactoryrelease of gas pressure in the container when opened to conduct anypressure gas passing through aperture 18 regardless of tear striplocation or direction on the outer cap which will be presentlydescribed.

As a practical example of' this in the invention embodiment of FIGS.l-3, it has been found through trials that the grooves 19 need notexceed sixty thousandths of an inch in depth and width to functionsuitably. The central aperture 18 is relatively small in size (diameter)and serves to direct and convey the gas pressure into the channel means(grooves 19) in the outer surface of disc-like portion 14, which, inturn, provides immediate and effective release of any gas pressure inthe container regardless of where in the outer metal cap thebreakthrough of the tear strip opening device is initiated. In otherwords, satisfactory release of gas pressure may occur at any placearound the periphery of the top area of the metal cap.

An additional feature of the liner cap includes the continuous annularchannel or grooves 20. This groove 20 connects with each of the radialgrooves 19 and serves to equalize gas pressure effectively and rapidlywithin the channel means network. If for any reason a groove 19 maybecome obstructed, the annular channel 20 equalizes pressure in all ofthe grooves.

The channel grooves may be molded in the liner cap during its formationor otherwise provided by casting, cutting, stamping, etc.

As shown on the drawings, FIGS. 1, 3, 4 and 6, the outer cap member 21is preferably made of metal, such as aluminum or tin plate ofappropriate gaugeor thickness, adapted to be crimped or secured aroundbead 11 of the container and sealingly attach the liner cap and outercap members about the container mouth. Outer cap 21 has a peripheralskirt 22 ending in a rolled lower edge or wire 23. The wire 23 may bebumped or formed in an initial assembly of liner cap 13 into outer cap21 so as to retain the two for feeding closures onto the containers incapping them. The skirt 22 integrally joins with corner radius portion24 and it in turn is integrally joined with periphery of the top panelof outer closure cap 21. A tear strip 29 is formed in top panel 21,across corner radius 24 and skirt 22 by a continuous score line 30 (FIG.1). The score line is formed by working the metal to reduce thethickness along a line. The score will increase the tendency of themetal to shear along the line so that the strip 29 may be peeled back bya pull tab or ring 25. The pull ring 25 is fastened to tear strip 29 bya rivet means 26 near the forward end of the tear strip, and a yokeportion 27 of the pull ring receives the rivet.

Liner cap 13 fits beneath the outer cap 21 and the skirt 22 iscompressed in capping to seal the skirt against the finish head 11, asshown on FIGS. 3 and 6. After sealing the container 10, pressure buildsinternally which bleeds through aperture 18 and fills the network ofgrooves 19, to pressurize the space in the channels at substantially thesame pressure as the container. Outer cap 21 need not be oriented toliner cap 13 to register the vent opening and tear strip 29 openingarea. In the present invention, the network of' grooves 19 will connectunder the tear strip 29 opening point and rupture of the tear strip atthe rivet or 37 pop area releases the pressure in the grooves andconducts further gas pressure from the container to atmosphere. Withpressure being equalized in initial opening, tear strip 29 may be tornfrom outer cap 21 to release it from the container; whereupon liner cap13 is removed and container product is ready for use.

Another embodiment of the invention is shown on FIGS. 4-6. The sameouter cap 21 may be employed. The liner cap 13 has on its outer surfaceof the disclike portion 14 a series of spoke oriented raised ribs 28.Between the adjacent pairs of ribs 28 there is formed a channelconveying pressure gas from aperture 18 into these spaces and underlyingthe point for opening the tear strip 29. the ribs preferably do notextend to the corner radius 16 and thereby create an annular passageway31 interconnecting all of the spaces between ribs for pressure gas flow.In this respect, the function provided by the groove 20 (FIGS. 1-3) issimilarly accomplished. The inner ends of the radial ribs 28 are spacedradially slightly from aperture 18 and the inner ends of the spacingbetween ribs are each interconnected.

It is suitable, although not shown on the drawings, to achieve theventing aspect of the invention by providing in place of the radial ribs28 a series of knobs or projections extending upwardly from the portion14 of the liner cap. These, as do the ribs 28, hold the outer metal cap21 spaced from the portion 14 of the liner cap 13' and provide passagesthroughthe top mouth area of the container closure for venting releaseof gas pressure conducted through the central aperture 18 as the metalouter convenience cap is being opened and removed.

The channel means structures herein described are easily formed in theplastic of liner cap 13 or 13'. The ribs or knobs, as the case may be,on the outer surface of the liner cap top panel 14 need not exceed sixtythousandths of an inch in height.

While a number of specific embodiments of the invention have beendescribed in detail or shown on the drawings, it should be apparent thatvarious other modifications could readily be made. Further, specificelements of the described embodiments could readily be combined indifferent configurations than those illustrated or described withoutdeparting from the spirit of the invention.

Accordingly, while preferred embodiments have been illustrated, itshould be understood that it is not intended the invention benecessarily restricted solely thereto, but we intend to include allembodiments thereof which would be apparent to those skilled in the art,and which come within the spirit of the scope of our invention asclaimed.

We claim:

1. A liner cap for a container closure adapted to telescope over theannular mouth defining rim of a container, said cap comprising a topportion, an annular skirt and a corner radius portion integrally,peripherally joining the top portion and the upper end of said annularskirt portion, a vent aperture through said top portion and disposed inthe central area of said top portion, radial channel means on the outersurface of said top portion extending radially toward said corner radiusportion and connecting with said aperture for conducting vented pressuremedia from said aperture radially outwardly of said top portion, saidradial channel means comprising plural radial grooves depressed in theouter surface of said top portion, and an annular groove formed in theouter surface of said top portion and disposed in the outer peripheralarea of said top portion, the plural grooves being connected into saidannular groove and having each of their radially inwardly disposed endsconnected to said vent aperture to receive vented media therefrom.

2. the liner cap defined in claim 1, wherein said aperture is located atthe center of said top portion.

3. The liner cap defined in claim 1, wherein said plural radial groovesare disposed at equal angular intervals about said top portion.

4. The liner cap defined in claim 1, including a depressed well area inthe outer surface of said top portion, said aperture extending throughthe top portion in said well area, and each of the radial groovesconnecting into said well area.

5. The liner cap defined in claim 4, wherein said well area comprises acircular well and the aperture is centrally located therein.

6. The liner cap defined in claim 1, in which said cap is formed from aplastic material.

7. The liner cap defined in claim 6, wherein said plastic materialcomprises polyethylene.

8. A liner cap for a container closure adapted to telescope over theannular mouth defining rim of a container, said cap comprising a topportion, an annular skirt and a corner radius portion integrallyperipherally joining the top portion and the upper end of said annularskirt portion, a vent aperture through said top portion and disposed inthe central area of said top portion, and plural, spaced, radial ribs onthe outer surface of said top portion, said ribs forming a spacedtherebetween from said aperture outwardly and radially therefrom forpassage of vented media from the aperture, said ribs at their outerradial ends being spaced inwardly in said top portion from said cornerradius portion of the cap.

9. The liner cap defined in claim 8, wherein said plural ribs defineplural channels along the outer surface of said top portion, the ribsbeing spaced at their inner radial ends from said aperature and eachother, said channels being interconnected to each other near saidaperture.

10. A closure for sealing the mouth opening of a container, said mouthbeing formed by a finish rim of the container, comprising a liner caphaving a disc-like portion covering the mouth opening of the container,said liner being comprised of an elastomeric material, a vent means inthe central area of said disc-like portion for conducting vented mediarelative to the interior of the container, plural radially extendinggrooves in the outer surface of said disc-like portion extending fromthe proximity of said vent means and extending radially toward theperimeter of said disc-like portion, an endless annular groove in saiddisc-like portion disposed near the outer ends of said radial grooves,said annular groove and said radial grooves being interconnected fortransmission of vented media, a cap having a top portion overlying thedisc-like portion of said liner cap and a radial annular integral skirtportion surrounding the finish rim and securing the closure on thecontainer, and a rupturable convenience-opening tear strip formed insaid top portion of the cap, said strip traversing at least one of saidplural radial grooves in the underlying liner cap.

11. The closure defined in claim 10, wherein each said groove is formedin said disc-like portion outer surface and is semi-circular incross-sectional configuration.

12. The closure defined in claim 10, wherein said radial grooves aredisposed at equal angular intervals about said disc-like portion.

13. The closure defined in claim 10, wherein the elastomeric liner capis comprised of polyethylene and the outer said cap is comprised ofaluminum.

14. A closure for sealing the mouth opening of a container, said mouthbeing formed by a finish rim of the container, including an inner snapcap of elastomeric material comprising a top portion for covering themouth opening of the container, an annular skirt portion for encirclingsaid rim, and a corner radius portion defining a rim receiving groove,the radius portion being raised from said top portion and integrallyjoining said top and skirt portions, a vent means in the central area ofsaid top portion for conducting vented media therethrough relative tothe interior of the container, plural, spaced, radial ribs on the outersurface of said top portion, said ribs forming a space therebetween fromthe vent means, radially outwardly for conducting vented media from saidvent means, the outer radial ends of the ribs being spaced inwardly fromthe corner radius portion of the liner cap, an outer metal cap overlyingsaid liner cap and comprising a top panel and an annular integral skirtportion surrounding the finish rim and securing the closure on thecontainer, and a rupturable convenience-opening tear strip formed insaid top portion of the outer cap including means for tear removal ofsaid tear strip from said top portion, said plural ribs of the liner capbeing engageable with the underside of the top panel of said outer capproviding radial channel passages connected to said vent means and anannular channel provided about the outer periphery of the top portion ofthe liner cap, all of said radial passages being connected with theannular channel and said vent means, said tear strip traversing at leastone of said radial passages, whereupon the tear removal of said tearstrip immediately vents the media between said liner and outer caps toatmosphere.

I! t t

1. A liner cap for a container closure adapted to telescope over theannular mouth defining rim of a container, said cap comprising a topportion, an annular skirt and a corner radius portion integrally,peripherally joining the top portion and the upper end of said annularskirt portion, a vent aperture through said top portion and disposed inthe central area of said top portion, radial channel means on the outersurface of said top portion extending radially toward said corner radiusportion and connecting with said aperture for conducting vented pressuremedia from said aperture radially outwardly of said top portion, saidradial channel means comprising plural radial grooves depressed in theouter surface of said top portion, and an annular groove formed in theouter surface of said top portion and disposed in the outer peripheralarea of said top portion, the plural grooves being connected into saidannular groove and having each of their radially inwardly disposed endsconnected to said vent aperture to receive vented media therefrom.
 1. Aliner cap for a container closure adapted to telescope over the annularmouth defining rim of a container, said cap comprising a top portion, anannular skirt and a corner radius portion integrally, peripherallyjoining the top portion and the upper end of said annular skirt portion,a vent aperture through said top portion and disposed in the centralarea of said top portion, radial channel means on the outer surface ofsaid top portion extending radially toward said corner radius portionand connecting with said aperture for conducting vented pressure mediafrom said aperture radially outwardly of said top portion, said radialchannel means comprising plural radial grooves depressed in the outersurface of said top portion, and an annular groove formed in the outersurface of said top portion and disposed in the outer peripheral area ofsaid top portion, the plural grooves being connected into said annulargroove and having each of their radially inwardly disposed endsconnected to said vent aperture to receive vented media therefrom. 2.the liner cap defined in claim 1, wherein said aperture is located atthe center of said top portion.
 3. The liner cap defined in claim 1,wherein said plural radial grooves are disposed at equal angularintervals about said top portion.
 4. The liner cap defined in claim 1,including a depressed well area in the outer surface of said topportion, said aperture extending through the top portion in said wellarea, and each of the radial grooves connecting into said well area. 5.The liner cap defined in claim 4, wherein said well area comprises acircular well and the aperture is centrally located therein.
 6. Theliner cap defined in claim 1, in which said cap is formed from a plasticmaterial.
 7. The liner cap defined in claim 6, wherein said plasticmaterial comprises polyethylene.
 8. A liner cap for a container closureadapted to telescope over the annular mouth defining rim of a container,said cap comprising a top portion, an annular skirt and a corner radiusportion integrally peripherally joining the top portion and the upperend of said annular skirt portion, a vent aperture through said topportion and disposed in the central area of said top portion, andplural, spaced, radial ribs on the outer surface of said top portion,said ribs forming a spaced therebetween from said aperture outwardly andradially therefrom for passage of vented media from the aperture, saidribs at their outer radial ends being spaced inwardly in said topportion from said corner radius portion of the cap.
 9. The liner capdefined in claim 8, wherein said plural ribs define plural channelsalong the outer surface of said top portion, the ribs being spaced attheir inner radial ends from said aperature and each other, saidchannels being interconnected to each other near said aperture.
 10. Aclosure for sealing the mouth opening of a container, said mouth beingformed by a finish rim of the container, comprising a liner cap having adisc-like portion covering the mouth opening of the container, saidliner being comprised of an elastomeric maTerial, a vent means in thecentral area of said disc-like portion for conducting vented mediarelative to the interior of the container, plural radially extendinggrooves in the outer surface of said disc-like portion extending fromthe proximity of said vent means and extending radially toward theperimeter of said disc-like portion, an endless annular groove in saiddisc-like portion disposed near the outer ends of said radial grooves,said annular groove and said radial grooves being interconnected fortransmission of vented media, a cap having a top portion overlying thedisc-like portion of said liner cap and a radial annular integral skirtportion surrounding the finish rim and securing the closure on thecontainer, and a rupturable convenience-opening tear strip formed insaid top portion of the cap, said strip traversing at least one of saidplural radial grooves in the underlying liner cap.
 11. The closuredefined in claim 10, wherein each said groove is formed in saiddisc-like portion outer surface and is semi-circular in cross-sectionalconfiguration.
 12. The closure defined in claim 10, wherein said radialgrooves are disposed at equal angular intervals about said disc-likeportion.
 13. The closure defined in claim 10, wherein the elastomericliner cap is comprised of polyethylene and the outer said cap iscomprised of aluminum.